Today, the small amount of materials removed in pulsed laser ablation is typically determined by depositing them on a quartz microbalance and measuring the shift in the quartz oscillator frequency. The method has many shortcomings: the instrumentation is costly, the smallest mass it can measure is fractions of nano-gram, and it generally requires operation in vacuum. Therefore, an inexpensive method with mass sensitivity down to tens of pico-gram and compatible with ambient air is desired.